We have been studying the chemical, rheological and mucociliary transport properties of canine tracheal mucus obtained from the pouch model. We propose to extend the physicochemical studies to purified canine tracheal mucins to elucidate the relation between the mucin structure and its rheological function and transport on the frog palate model. We also proposed to study the variables affecting mucus transport on the frog palate. Mucus from normal dogs as well as from dogs exposed to pharmacological agents known to affect mucus secretion will be studied. Finally, we will initiate a program to extend the studies to human ear mucus obtained from patients with secretory otitis media. The results of these studies should lead to a better understanding of the physicochemistry of mucociliary flow and its important role in obstructive pulmonary disease.